Strontium drinking water

The average annual concentration of beta particle and photon radioactivity from man-made radionuclides in drinking water shall not produce an annual dose equivalent to the total body or any internal organ greater than 4 millirem/yr. Tritium must be less than 20,000 pCi L-1, and strontium must be less than 8 pCi L-1. 

Most of the strontium in water is dissolved. Strontium in water comes from different sources. Most of it comes from dissolving strontium out of rocks and soil that water runs over and through. Only a very small part is from the settling of strontium dust out of the air. Some strontium is suspended in water, as in muddy water. The amount of strontium that has been measured in drinking water in different parts of the United States by the EPA is generally less than... 

If a person breathes in vapors or dust containing a strontium chemical that is soluble in water, then the chemical will dissolve in the moist surface inside the lungs and strontium will enter the bloodstream relatively quickly. If the strontium chemical does not dissolve in water easily, particles may rest inside of the lung for a time. When you eat food or drink water that contains strontium, only a small portion leaves the intestines and enters the bloodstream. In young people, a larger portion enters the bloodstream than in adults. If a fluid mixture of a strontium chemical is... 

The total estimated daily exposure to stable strontium is approximately 3.3 mg/day 400 ng/day from inhalation, 2 mg/day from drinking water, and 1.3 mg/day from the diet (see Chapter 6). Assuming a reference body weight of 70 kg, the typical daily strontium exposure is 46 pg/kg body weight. The strontium content of the human body is approximately 4.6 ppm by weight, 99% of which is localized in bones and teeth. Blood concentrations of strontium are in the range of 20-31 pg/L. 

Radioactive Strontium. In the Techa River population that was exposed to radiostrontium and radiocesium in drinking water and food between 1949 and 1956, an increase in the number of deaths from leukemia and solid cancers was reported (Kossenko 1996). In the exposed group, the standardized mortality rate was 140 (95% Cl 131-150) per 100,000 compared to 105 (95% Cl 101-109) per 100,000 in the control group during the followup period (1950-1982). Absorbed doses to the red bone... 

Radioactive Strontium. No studies were located regarding renal effects in humans after oral exposure to radioactive strontium isotopes. Approximately 19% of adult Long-Evans rats ingesting 65 pCi 90Sr/day (2.41 MBq/day 135 or 194 pCi/kg/day, 5 or 7.2 MBq/kg/day for males and females, respectively) of in drinking water for 10 days developed chronic interstitial nephritis, a common disease in older rats, during their remaining lifespan (Casarett et al. 1962). 

Information on the distribution of strontium in soft tissue is extremely limited. In rats that were exposed to 3. 4 mg strontium/L (as SrCl2) in drinking water for 3 months, the serum concentration of strontium was 8.7 mg/L and tissue serum strontium concentration ratios (based on the latter mean serum concentration) were as follows liver, 0.7 heart, 1.2 muscle, 1.1 adrenal, 1.3 brain, 1.2 and bone, 1,300 (Skoryna 198 lb). Strontiumxalcium ratios in these tissues were approximately 0.05-0.1. Tissue plasma strontium concentration ratios in rats 1-5 hours after they received an intraperitoneal injection of strontium revealed ratios <1 in the fat, spleen, liver, ovary, testis, skeletal muscle, and heart and values of 1.2-1.7 in the lung, small intestine, salivary gland, kidney, and skin (Brues et al. 1969). Tissue plasma concentration ratios of... 

Exposure Levels in Humans. The primary source of recent information on the occurrence of 90Sr in drinking water is the National Inorganics and Radionuclides Survey conducted by EPA. Better and more recent information on background levels in the environment (e.g., air, food, water, and soil) may be useful. Additional information on bioavailability of strontium and radiostrontium from environmental media is necessary. 

Toxic effects may be expected from an Sr content of > 300 mg kg in the skeleton of rats (Seifert 1998). Feeding experiments with strontium carbonate in rats reduced the calcification of teeth, bones, and cartilage (Nagayama etal. 1984). Similar symptoms were observed in humans in the case of endemic chondrodystrophy occurring in Tadzhikistan, and this is assumed also to occur in farm animals. Strontium levels > 1 g kg in soil and 50 mg L in drinking water were recorded in habitats with a high Sr availability in the food chain (Kovalskij 1977). 

Beverages provide humans with 28% of their magnesium intake, 27% of nickel, 24% of copper, 33% of strontium, 40% of uranium, 45% of rubidium, and 58% of vanadium consumption. Drinking water, home-made beverages (tea, coffee) and beer are important suppliers of inorganic body components. 

Barium belongs among the toxic elements. The content of strontium in drinking water is not the subject of an official standard. Strontium present in mineral waters has favourable effects when used for the treatment of skin diseases and also for the treatment of respiratory diseases. 

EPA uses its Clean Air Act authority to set limits on the amount of radionuclides, such as Sr-90. that may be released to the air. EPA s Superfund Hotline 1-800-424-9346 or 1-800-535-0202 EPA uses its Safe Drinking Water Act authority to establish maximum contaminant levels (MCLs) tor beta emitters, such as strontium-90, in public drinking water. The MCL for beta emitters is 4 millirem per year or 8 picoCuries per liter of water. 

I. Sato, H. Kudo, S. Tsuda, Removal efficiency of water purifier and adsorbent for iodine, cesium, strontium, barium and zirconium in drinking water, J. Toxicol. Sci. 36, 2011, 829-834. 

Dental surveys suggest that the low prevalence of caries has a curvilinear relation to the strontium concentrations in drinking water. However, the combination of strontium and fluoride appears to be necessary for a maximum reduction in caries. The strontium fluorapatite that is formed has a greater resistance to dissolution than the original calcium hydroxyapatite [65]. 

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